Image pickup apparatus and endoscope

Abstract

An image pickup apparatus includes a solid-state image pickup device chip, an FPC whose terminals are connected to the solid-state image pickup device chip, and a plurality of electronic components mounted on a front surface of the FPC, wherein behind a back face of the solid-state image pickup device chip, the FPC is disposed by being folded in such a way that the FPC will provide mounting surfaces for the plurality of electronic components in a plurality of layers and that the plurality of electronic components will be superimposed via the FPC.

What is claimed is: 
     
         1 . An image pickup apparatus comprising:
 a solid-state image pickup device chip;   a flexible printed circuit board connected at one end to the solid-state image pickup device chip,
 wherein, in an unfolded state, the flexible printed circuit board has a first surface facing a first direction along a layering axis, and a second surface facing a second direction opposite to the first direction along the layering axis, 
 wherein in the flexible printed circuit board comprises:
 a first portion defining a primary mounting region, wherein the first portion has a first end and a second end defining a longitudinal axis of the first portion, and wherein the longitudinal axis is perpendicular to the layering axis; 
 a second portion defining one or more secondary mounting regions and one or more deformation regions, wherein each of the one or more deformation regions extend along a corresponding folding axis that is parallel to the longitudinal axis of the first portion; and 
 a third portion defining a thirdly mounting region, wherein the third portion extends along the longitudinal axis from at least the second end of the first portion with other deformation region intervened, 
 
 wherein, in a folded state, the second portion of the flexible printed circuit board is folded in the one or more deformation regions along the corresponding folding axis and at least a part of the third portion is folded with the other deformation region deformed such that the primary mounting region, the one or more secondary mounting regions, and at least the part of the thirdly mounting region are layered along the layering axis, and 
 wherein, in the folded state, the thirdly mounting region is located in a region separate from the primary mounting region and the one or more secondary mounting regions with deformation of the other deformation region; 
   a plurality of electronic components mounted on the first surface of the flexible printed circuit board in the primary mounting region and the one or more secondary mounting regions,   wherein a lead wire connecting portion is mounted on the first surface or the second surface in the thirdly mounting region to be connected with lead wires of a signal cable which transmits an electrical signal of an image picked up on an image pickup surface of the solid-state image pickup chip to an external apparatus,   wherein each of the plurality of electronic components mounted on different ones of the primary mounting region and the one or more secondary mounting region, and the lead wire connecting portion mounted in the thirdly mounting region are insulated to be out of direct contact with each other in the primary mounting region, the one or more secondary mounting regions, and the thirdly mounting region, by the flexible printed circuit board in the folded state,   wherein the second surface of the flexile printed circuit board has no electronic component mounted thereon, and   wherein in the folded state of the flexible printed circuit board, the lead wire connecting portion is located on an outermost layer.   
     
     
         2 . The image pickup apparatus according to  claim 1 , wherein the flexible printed circuit board provides mounting surfaces for the plurality of electronic components in three or more layers. 
     
     
         3 . The image pickup apparatus according to  claim 1 , wherein:
 the solid-state image pickup chip makes up a package unit in conjunction with a connecting portion to which the flexible printed circuit board is connected at the one end and cover glass which protects the image pickup surface by being affixed to the image pickup surface; and   the flexible printed circuit board is disposed in such a position as to be superimposed over the package unit when seen in planar view from the image pickup surface.   
     
     
         4 . The image pickup apparatus according to  claim 1 , wherein the flexible printed circuit board is disposed by being inclined at a predetermined angle with respect to the back face of the solid-state image pickup chip. 
     
     
         5 . The image pickup apparatus according to  claim 1 , wherein the electronic component smaller than a predetermined size is disposed in a region surrounded by the plurality of electronic components equal to or larger than the predetermined size when seen in planar view. 
     
     
         6 . The image pickup apparatus according to  claim 1 , wherein the electronic component smaller than a predetermined size is disposed in a region sandwiched by the plurality of electronic components equal to or larger than the predetermined size when seen in planar view. 
     
     
         7 . The image pickup apparatus according to  claim 6 , wherein the plurality of electronic components equal to or larger than the predetermined size are disposed in such a way as to sandwich the electronic component smaller than the predetermined size in a direction orthogonal to a folding direction of the flexible printed circuit board, when seen in planar view. 
     
     
         8 . The image pickup apparatus according to  claim 1 , wherein a mounting strength enhancement portion is formed in at least part of ends of the flexible printed circuit board in a direction perpendicular to a folding direction of the flexible printed circuit board to enhance mounting strength of the electronic components on the flexible printed circuit board in the folding direction of the flexible printed circuit board. 
     
     
         9 . The image pickup apparatus according to  claim 8 , wherein the electronic component smaller than the predetermined size is disposed near the mounting strength enhancement portion. 
     
     
         10 . The image pickup apparatus according to  claim 1 , wherein part of the plurality of electronic components is mounted, on one side of the flexible printed circuit board, in a region folded in a second folding direction different from a first folding direction which is the folding direction. 
     
     
         11 . The image pickup apparatus according to  claim 1 , wherein the flexible printed board has the shape fixed by an adhesive in the folded state. 
     
     
         12 . The image pickup apparatus according to  claim 1 , wherein, in the folded state of the flexible printed circuit board, the lead wire connecting portion is located on a bottom layer. 
     
     
         13 . The image pickup apparatus according to  claim 1 , wherein, in the folded state of the flexible printed circuit board, the lead wire connecting portion is exposed outward. 
     
     
         14 . The image pickup apparatus according to  claim 1 , wherein, in the folded state of the flexible printed circuit board, a part of the lead wire connecting portion is located along the layering axis. 
     
     
         15 . The image pickup apparatus according to  claim 4 , wherein, in the folded state of the flexible printed circuit board, a part of the lead wire connecting portion extends to be inclined at the predetermined angle with the flexible printed circuit board. 
     
     
         16 . The image pickup apparatus according to  claim 1 , wherein, in the folded state of the flexible printed circuit board, the electronic component mounted on the first surface in the one or more secondary mounting regions is in contact with one of the first surface and the second surface, on which the lead wire connecting portion is not mounted, in the thirdly mounting region. 
     
     
         17 . The image pickup apparatus according to  claim 1 , wherein one or more third mounting regions are provided, and one or more other deformation regions are provided. 
     
     
         18 . An endoscope comprising:
 a solid-state image pickup device chip;   a flexible printed circuit board connected to the solid-state image pickup device chip,
 wherein, in an unfolded state, the flexible printed circuit board has a first surface facing a first direction along a layering axis, and a second surface facing a second direction opposite to the first direction along the layering axis, 
 wherein in the flexible printed circuit board comprises:
 a first portion defining a primary mounting region, wherein the first portion has a first end and a second end defining a longitudinal axis of the first portion, and wherein the longitudinal axis is perpendicular to the layering axis; 
 a second portion defining one or more secondary mounting regions and one or more deformation regions, wherein each of the one or more deformation regions extend along a corresponding folding axis that is parallel to the longitudinal axis of the first portion; and 
 a third portion defining a thirdly mounting region, wherein the third portion extends along the longitudinal axis from at least the second end of the first portion with other deformation region intervened, 
 
 wherein, in a folded state, the second portion of the flexible printed circuit board is folded in the one or more deformation regions and the other deformation region along the corresponding folding axis and at least a part of the third portion is folded with the other deformation region deformed such that the primary mounting region, the one or more secondary mounting regions, and at least the part of the thirdly mounting region are layered along the layering axis, and 
 wherein, in the folded state, the thirdly mounting region is located in a region separate from the primary mounting region and the one or more secondary mounting regions with deformation of the other deformation region; 
   a plurality of electronic components mounted on the first surface of the flexible printed circuit board in the primary mounting region and the one or more secondary mounting regions,   wherein a lead wire connecting portion is mounted on the first surface or the second surface in the thirdly mounting region to be connected with lead wires of a signal cable which transmits an electrical signal of an image picked up on an image pickup surface of the solid-state image pickup chip to an external apparatus,   wherein each of the plurality of electronic components mounted on different ones of the primary mounting region and the one or more secondary mounting region, and the lead wire connecting portion mounted in the thirdly mounting region are insulated to be out of direct contact with each other in the primary mounting region, the one or more secondary mounting regions, and the thirdly mounting region, by the flexible printed circuit board in the folded state,   wherein the second surface of the flexible printed circuit board has no electronic component mounted thereon, and   wherein in the folded state of the flexible printed circuit board, the lead wire connecting portion is located on an outermost layer.